Interactions between eye and head control signals can account for movement kinematics

Advances in understanding the neural control of saccades (visual orienting movements made when the head is prevented from moving) stem largely from early modeling efforts which provided a framework for developing and testing hypotheses about the relationships between neural activity and observed behaviors. When the head is free to move, visual orienting is often accomplished with coordinated movements of the eyes and head. A recent description of the temporal progression (i.e., kinematics) of these movements led to the hypothesis that eye and head control signals interact. This hypothesis is now formalized as a control systems model which accounts for existing data and makes explicit predictions about the neural control of orienting gaze shifts.